The present invention relates to ball valves and more particularly to a ball valve that includes a vacum-creating venturi wherein the venturi is within the ball of the valve.
There are many applications where a fluid is stored in a tank until delivery of measured quantities of the fluid is desired. Delivery of a fluid from such a tank can be accomplished in various ways including the use of a pump of a venturi valve system. Pumps require a separate power source and a venturi system requires a flowing fluid with which the fluid to be delivered from the tank is mixed before it is discharged.
In applications where the mixing of the stored fluid with the flowing fluid is at least not detrimental or where it is desirable, the use of a venturi valve system is attractive. A venturi system is a passive device that is generally smaller in size, uses less power, is less complex and is lighter in weight than a pump. In aerial spraying applications it is necessary to atomize the chemicals to be sprayed. In such an application, the forward motion of the aircraft creates a fluid flow with respect to the aircraft, namely air flow, which may be utilized as the ram fluid in a venturi evacuatio system, as well as providing the air necessary to atomize the chemicals for spraying. By proper selection of the cross-sectional area of the venturi and the supply line from the tank of fluid to be evacuated, the desired mixture of air and evacuated fluid can be achieved. In the prior art, the valves in either or both fluid paths are independent of the venturi creating device which creates the necessary vacuum for evacuating the fluid from the tank.
It would prove useful to have a valve with the usual shut-off characteristics which incorporates a venturi chamber therewithin. Such a device could also prove useful as a fluid pressure amplifier when the outlet port is closed and the venturi chamber is in the normal position. The present invention provides such a device.